Tinnitus can sound like a roaring in the ears, according to the National Institute on Deafness and Other Communication Disorders. While it typically manifests as a ringing in the ears, it can also sound like buzzing, clicking or hissing and can occur at any pitch.
Tinnitus is a sign of problems in the auditory system, as the National Institute on Deafness and Other Communication Disorders explains. It can result from excessive earwax, sinus infections, brain tumors, hearing loss resulting from excess noise, and other causes. The problem is really one of the auditory circuits in the brain, not of the ear apparatus itself, and scientists don't agree on the process that creates tinnitus.